The present invention relates to a device and a method for handling ink drops, particularly for receiving ink drops from a printhead or a printhead cleaning unit and discharging the ink drops into an ink drop collection tray.
It is known to collect ink drops falling down from a printhead or a printhead cleaning unit in a collection tray. The ink drops fall in a liquid condition and set or become rigid in the collection tray, thereby possibly forming stalagmites. These stalagmites may cause a problem in that they may interfere with the movement of the printhead or the cleaner. An operator must be available to periodically and timely remove the stalagmites.
It is further known to intercept the ink drops falling down from a printhead or a cleaning unit by using a belt conveyor which, in a forward track, runs from a location of receiving ink drops to a location of discharge or delivery of the ink drops to a collection tray or the like. At the location of discharge, the conveyor belt turns in an opposite direction in a backward track with the solidified ink drops being taken along. At the lower side of the conveyor belt, after the turning area, a stationary scraper is provided to engage the ink drops attached to the conveyor belt and scrape them from the conveyor belt. A disadvantage of this known arrangement is that the scraper, in order to function reliably, must engage the belt surface causing the belt surface to experience considerable wear and tear.
In a further known arrangement the ink drops falling down are received by a conveyor belt that circulates about four rollers arranged in a vertical square: one upper roller, one lower roller and two side rollers. Considered in a cross-section of the belt, the upper roller has a concave belt supporting surface and the lower roller has a convex belt supporting surface. The concave portion of the belt forms a trough for the ink drops. By the outward flexing of the belt, as considered in cross-section, towards the convex shape, the ink drops on the belt are loosened in order to fall on the bottom wall of the refuse chamber in which the arrangement is positioned below an ink drop inlet arranged in the upper wall thereof. Although the intention here is to loosen the ink drops by the conversion of the shape of the ink drop support surface, that is the belt, which might result in a simple structure, some ink drops, nonetheless, remain attached to the conveyor belt.
Therefore, there is a need for a device for receiving ink drops from a printhead or a printhead cleaning unit and discharging the ink drops into an ink drop collection tray with improved reliable performance. In addition, there is a need for a method for receiving ink drops from a printhead or a printhead cleaning unit and discharging the ink drops to an ink drop collection tray with improved, reliable performance.